
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}


li {
    list-style: none;
}

main {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100vw;
    height: 100vh;
    position: relative;
    background: #2c3a47;
    z-index: 25;
}

ul {
    display: flex;
}

ul li {
    margin: 0 18px;
}

li a {
    position: relative;
    display: block;
    color: white;
    width: 64px;
    height: 64px;
    font-size: 36px;
    text-align: center;
    line-height: 66px;
    border-radius: 50%;
    background: #2c3a47;
    transition: 0.6s;
}

li a:hover {
    text-shadow: 0 0 4px #25ccf7;
}

li a::before {
    content: "";
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    border-radius: 50%;
    background: #25ccf7;
    transition: 0.6s;
    transform: scale(0.8);
    z-index: -1;
}

li a:hover::before {
    box-shadow: 0 0 14px 2px #25ccf7;
    transform: scale(1.05);
}

@media screen and (max-width: 512px) {
    ul {
        flex-direction: column;
    }

    ul li {
        margin: 18px 0;
    }
}


